August water use to date

9 billion litres

9 billion litres

Dam storage levels


48 per cent

Weekly streamflow into dams


20 billion litres

August rainfall to date

122.1 mm

(August average rainfall 1994-2017)

31.49 mm

Note: 1 billion litres = approx. 400 Olympic swimming pools. Please note the figures in this table are rounded (except for rainfall) to the nearest whole number.












Water use


Average water use over the last week was 585 million litres per day, which was above the forecast of 567 million litres.


Daily water use for the last five days


Actual water use (million litres)

Forecast (million litres)
















Note: water use is calculated up to 8am each day for the previous 24 hour period


Since 1 July 2019, we have used 26.7 billion litres of water – which is just over the forecast for this period.


Dam level (total for 15 dams)

The dam storage levels have remained stable this week and are sitting at a combined 47.8 per cent* of full capacity.


*Please note some dams are filled from different sources - dam levels include the transfer of groundwater and desalinated seawater from treatment plants as well as streamflow (that comes from rainfall).  As we use many different sources of water, dams are no longer an accurate indicator of the health of Perth's overall water supply situation.

Streamflow (total for 15 dams)


From 1 May 2019 the dams have received 19.6 billion litres of streamflow.  The post-1975 average for the May to April period (called the streamflow year) is 187.2 billion litres.


Sprinkler roster compliance


The Winter Sprinkler Switch-off is now in place. This means you need to ensure your sprinklers are kept switched off until the end of winter.


Our team of inspectors issued 130 warnings and 18 fines this week.  Since 1 January 2019, we have taken a total of 5748 actions (warnings + fines) compared with 5821 actions for the same period in 2018.


Annual rainfall


Perth has received 427.69 mm of rainfall since 1 January 2019.  The cumulative average (1994-2017) rainfall for the January to August period is 572.2 mm.


General water news


Did you know almost 70 per cent of all water used in Perth comes from groundwater?!

Groundwater is a crucial part of the water cycle and our natural environment. The hidden resource comes from rain soaking through the soil into aquifers, which are not the underground lakes or rivers you might imagine – but rather rock material with enough connected space to store and move water through it.

Since 1975, Perth’s average rainfall has declined by 15 per cent due to climate change, which means there is less water soaking into our aquifers, and less groundwater to share.

We all use groundwater for things like growing local produce, watering our gardens, parks, ovals and public spaces, and we treat it to supply drinking water.

This means we all have a role to play in using it wisely.

Groundwater is currently featured in a joint ‘Be Groundwater Wise’ education campaign with Water Corporation and the Department of Water and Environmental Regulation to raise awareness of its importance.

Find out more about Perth’s groundwater at


Media Enquiries:

Contact: Clare Lugar

Position: Manager Media and Strategic Communications

Phone: (08) 9420 2555